Most of the Youtube videos do not fillup my entire screen

I am not sure if this has already been posted, tried searching the WEB but did not find a sutiable solution.

I have a logitech revue connected to my Acer 24 inch LCD monitor via HDMI. When I play
certain videos on youtube, they do not fillup my entire screen, black bars appear on both sides (even if I click on "fullscreen" button on the video player). I believe this is because the original video file is in 4:3 format vs. 16:9 of my LCD. However the same video stretches to fill up the screen when I play it on my laptop connected to this monitor.

On the laptop I can right click a youtube video & uncheck "enable hardware acceleration" option in the flashplayer settings. Can this be done on the revue? I am not sure if this will fix the problem.

Please help (I hate to watch the black bars appearing on either sides of the screen).